Chair assemblies of the type used in chairlifts for skiing and sight-seeing typically are bench-type chairs which are mounted by a hanger arm from a haul rope. They usually are open to the elements or provide no protection against the cold and precipitation for the passengers. At various times, attempts have been made to partially enclose chairlift chair assemblies with transparent plastic bubbles, but this has posed substantial problems, particularly in the skiing industry. The enclosure must be movable to permit ingress and egress from the chair by passengers without special preparation and without stopping movement of the chairs. Thus, skiers must be able to get on and off the chair with their equipment on and while the chair is moving.
The approach which generally has been taken to the problem of enclosing chair assemblies has been to movably mount a plastic bubble to the chair and employ a lever system which can be actuated automatically at the end terminals of the chairlift to move the bubble enclosure between open and closed positions. Thus, a lever or arm is mounted on a movable enclosure, which arm will engage a force applying structure at the terminal as the chair is advanced. The inter-engagement between the enclosure lever and the stationary terminal opening device causes the bubble to be moved, usually by pivoting, to an open position as the chair enters the terminal. This permits the passengers to exit or enter the chair. As the chair leaves the terminal, a similar closure structure engages the same, or another lever or arm on the chair, to lower the enclosure over the passengers. Usually, the passengers also have the ability to raise or lower the enclosure manually while seated in the chair.
One of the serious problems that can occur with such lever-actuated chairlift enclosure systems is that, if an obstruction or passenger should interfere with the opening or closing of the bubble, the forces generated can become quite high and dangerous. Thus, if the enclosure is being closed by a lever against an object being carried by the passenger, such as ski poles, the lever can jam the bubble against the poles and/or passenger. The result can be injury to a passenger, bending of the poles, bending of the chair opening and closing components, or a combination of these problems.
An additional problem has been encountered in connection with the chairlift chair assemblies having movable bubble-type enclosures. In the open position the enclosures are extremely bulky. One typical prior art enclosure assembly is pivoted at the back of the chair so that the enclosure moves to an open position which extends outwardly of the chair by a substantial amount. This type of structure can make it difficult for the bubble to pass beyond the hanger arm, can pose excessive bulk problems in and around the terminal, and even undesirable aerodynamic drag during the opening and closing process. Retrofitting such a bulky structure to existing chair hanger arms, therefore, can be difficult or impossible.
Accordingly, it is an object of the present invention to provide chairlift chair assembly having a movable enclosure which obviates or minimizes the difficulties of the type previously described.